Touch sensor, touch sensor driving method, and display device

ABSTRACT

A touch sensor may include a substrate and may include electrode units, first demultiplexers, second demultiplexers, and driving pads all located on the substrate. The electrode units each may include a plurality of electrode groups, the electrode groups each including a plurality of touch electrodes. The first demultiplexers each may include a plurality of sub-demultiplexers and each may be electrically connected to a corresponding one of the electrode units. Each of the sub-demultiplexers of a first demultiplexer may be electrically connected to a corresponding one of the electrode groups of a corresponding electrode unit. The second demultiplexers may be connected between the first demultiplexers and the driving pads.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation application of U.S. patentapplication Ser. No. 17/491,404 filed Sep. 30, 2021, which is acontinuation application of U.S. patent application Ser. No. 16/915,946filed Jun. 29, 2020 (now U.S. Pat. No. 11,163,412), which is adivisional application of U.S. patent application Ser. No. 15/940,260filed Mar. 29, 2018 (now U.S. Pat. No. 10,732,775), which claimspriority to Korean Patent Application No. 10-2017-0041659, filed on Mar.31, 2017, in the Korean Intellectual Property Office; the entiredisclosure of the Korean Patent Application is incorporated by referenceherein.

BACKGROUND 1. Field

The technical field relates to a touch sensor, a driving method of thetouch sensor, and a display device including the touch sensor.

2. Description of the Related Art

Display devices may include touch sensors for receiving touch inputs ofusers in addition to display unit for displaying images. Users canconveniently control the display devices through the touch sensors.

Various types of touch sensors are available. For example, a capacitivetouch sensor senses a point at which capacitance is changed as a user'shand or object is in contact with the point, thereby detecting a touchposition.

SUMMARY

Embodiments may minimize the number of pads in a touch sensor by usingone or more demultiplexers.

An embodiment may be related to a touch sensor that includes thefollowing elements: a substrate; electrode units located on thesubstrate, the electrode units each including a plurality of electrodegroups; first demultiplexers located on the substrate, the firstdemultiplexers being respectively connected to the electrode units;driving pads located on the substrate; and second demultiplexers locatedon the substrate, the second demultiplexers being connected between thefirst demultiplexers and the driving pads, wherein each of the electrodegroups includes a plurality of touch electrodes, wherein each of thefirst demultiplexers includes sub-demultiplexers connected to theelectrode groups.

Each of the electrode units may include a first electrode group, asecond electrode group, a third electrode group, and a fourth electrodegroup.

The first electrode group and the third electrode group may be disposedadjacent to each other along a first direction. The second electrodegroup and the fourth electrode group may be disposed adjacent to eachother along the first direction.

The first electrode group and the second electrode group may be disposedadjacent to each other along a second direction intersecting the firstdirection.

The third electrode group and the fourth electrode group may be disposedadjacent to each other along the second direction.

The first electrode group and the third electrode group may be disposedon an ith (i is a natural number of 1 or more) column. The secondelectrode group and the fourth electrode group may be disposed on an(i+1)th column.

Each of the first demultiplexers may include a first sub-demultiplexerconnected to the first electrode group, a second sub-demultiplexerconnected to the second electrode group, a third sub-demultiplexerconnected to the third electrode group, and a fourth sub-demultiplexerconnected to the fourth electrode group.

Each of the second demultiplexers may electrically connect a firstsub-demultiplexer to a corresponding driving pad during a first period,electrically connect a second sub-demultiplexer to the driving padduring a second period, electrically connect a third sub-demultiplexerto the driving pad during a third period, and electrically connect afourth sub-demultiplexer to the driving pad during a fourth period.

The first sub-demultiplexer may sequentially connect touch electrodesincluded in the first electrode group electrically to the driving padduring the first period, the second sub-demultiplexer may sequentiallyconnect touch electrodes included in the second electrode groupelectrically to the driving pad during the second period, the thirdsub-demultiplexer may sequentially connect touch electrodes included inthe third electrode group electrically to the driving pad during thethird period, and the fourth sub-demultiplexer may sequentially connecttouch electrodes included in the fourth electrode group electrically tothe driving pad during the fourth period.

Operations of the first demultiplexers may be controlled by the samefirst control signals. Operations of the second demultiplexers may becontrolled by the same second control signals.

The touch sensor may further include: first control pads located on thesubstrate, the first control pads providing the first control signals tothe first demultiplexers; and second control pads located on thesubstrate, the second control pads providing the second control signalsto the second demultiplexers.

The touch sensor may further include: a first voltage pad located on thesubstrate; and third demultiplexers connected between the electrodeunits and the first voltage pad.

Each of the third demultiplexers may include sub-demultiplexersrespectively connected to different electrode groups.

The touch sensor may further include: a second voltage pad located onthe substrate; and fourth demultiplexers connected between the electrodeunits and the second voltage pad.

Each of the fourth demultiplexers may include sub-demultiplexersrespectively connected to different electrode groups.

The first voltage pad may provide a first voltage to the thirddemultiplexers, and the second voltage pad may provide a second voltageto the fourth demultiplexers. The first voltage may have a voltage valuehigher than the second voltage.

Operations of the third demultiplexers may be controlled by the samethird control signals. Operations of the fourth demultiplexers may becontrolled by the same fourth control signals.

The touch sensor may further include: third control pads located on thesubstrate, the third control pads providing the third control signals tothe third demultiplexers; and fourth control pads located on thesubstrate, the fourth control pads providing the fourth control signalsto the fourth demultiplexers.

The touch sensor may further include: a connecting member connected tothe driving pads; and a touch driving unit supplying a driving signal tothe driving pads through the connecting member.

An embodiment may be related to a method for driving a touch sensor. Themethod may include the following steps: sequentially supplying a drivingsignal to touch electrodes included in each first electrode group duringa first period; sequentially supplying a driving signal to touchelectrodes included in each second electrode group during a secondperiod; sequentially supplying a driving signal to touch electrodesincluded in each third electrode group during a third period; andsequentially supplying a driving signal to touch electrodes included ineach fourth electrode group during a fourth period, wherein the othertouch electrodes except the touch electrodes supplied with the drivingsignal during each period are supplied with a first voltage or a secondvoltage.

The first electrode groups and the third electrode groups may bedisposed along a first direction. The second electrode groups and thefourth electrode groups may be disposed along the first direction.

The first electrode groups and the second electrode groups may bealternately disposed along a second direction intersecting the firstdirection. The third electrode groups and the fourth electrode groupsmay be alternately disposed along the second direction.

The first electrode groups and the third electrode groups may bedisposed on odd-numbered columns. The second electrode groups and thefourth electrode groups may be disposed on even-numbered columns.

During each period, some electrodes among the other electrodes may besupplied with the first voltage, and other some electrodes among theother electrodes may be supplied with the second voltage.

The first voltage may have a voltage value higher than the secondvoltage.

An embodiment may be related to a display device that includes thefollowing elements: a substrate including a first region and a secondregion; pixels located on the first region; an encapsulation layerlocated on the pixels; electrode units located on the encapsulationlayer, the electrode units each including a plurality of electrodegroups; first demultiplexers located on the second region, the firstdemultiplexers being respectively connected to the electrode units;driving pads located on the second region; and second demultiplexerslocated on the second region, the second demultiplexers being connectedbetween the first demultiplexers and the driving pads, wherein each ofthe electrode groups includes a plurality of touch electrodes, whereineach of the first demultiplexers includes sub-demultiplexers connectedto the electrode groups.

The display device may further include a display driver located on thesecond region, the display driver driving the pixels.

Some of the first demultiplexers and some of the second demultiplexersmay be located at one side of the display driver. Other some of thefirst demultiplexers and other some of the second demultiplexers may belocated at the other side of the display driver.

The display device may further include: a connecting member connected tothe driving pads; and a touch driving unit supplying a driving signal tothe driving pads through the connecting member.

The display device may further include: a first voltage pad located onthe second region; and third demultiplexers located on the secondregion, the third demultiplexers being connected between the electrodeunits and the first voltage pad.

The display device may further include: a second voltage pad located onthe second region; and fourth demultiplexers located on the secondregion, the fourth demultiplexers being connected between the electrodeunits and the second voltage pad.

The first voltage pad may provide a first voltage to the thirddemultiplexers, and the second voltage pad may provide a second voltageto the fourth demultiplexers. The first voltage may have a voltage valuehigher than the second voltage.

An embodiment may be related to a touch sensor. The touch sensor mayinclude a substrate and may include electrode units, firstdemultiplexers, second demultiplexers, and driving pads all located onthe substrate. The electrode units each may include a plurality ofelectrode groups, the electrode groups each including a plurality oftouch electrodes. The first demultiplexers each may include a pluralityof sub-demultiplexers and each may be electrically connected to acorresponding one of the electrode units. Each of the sub-demultiplexersof a first demultiplexer may be electrically connected to acorresponding one of the electrode groups of a corresponding electrodeunit. The second demultiplexers may be connected between the firstdemultiplexers and the driving pads. The driving pads may beelectrically connected through the second demultiplexers to the firstdemultiplexers.

Each of the electrode units may include a first electrode group, asecond electrode group, a third electrode group, and a fourth electrodegroup.

The first electrode group and the third electrode group may be disposedadjacent to each other along a first direction, and

The second electrode group and the fourth electrode group may bedisposed adjacent to each other along the first direction.

The first electrode group and the second electrode group may be disposedadjacent to each other along a second direction different from the firstdirection. The third electrode group and the fourth electrode group maybe disposed adjacent to each other along the second direction.

The first electrode group and the third electrode group may be disposedon a first column. The second electrode group and the fourth electrodegroup may be disposed on a second column parallel to the first column.

Each of the first demultiplexers may include a first sub-demultiplexerelectrically connected to the first electrode group, a secondsub-demultiplexer electrically connected to the second electrode group,a third sub-demultiplexer electrically connected to the third electrodegroup, and a fourth sub-demultiplexer electrically connected to thefourth electrode group.

Each of the second demultiplexers may electrically connect the firstsub-demultiplexer to a corresponding driving pad during a first period,electrically connects the second sub-demultiplexer to the correspondingdriving pad during a second period, electrically connects the thirdsub-demultiplexer to the corresponding driving pad during a thirdperiod, and electrically connects the fourth sub-demultiplexer to thecorresponding driving pad during a fourth period.

The first sub-demultiplexer may sequentially connect touch electrodesincluded in the first electrode group electrically to the correspondingdriving pad during the first period. The second sub-demultiplexer maysequentially connect touch electrodes included in the second electrodegroup electrically to the corresponding driving pad during the secondperiod. The third sub-demultiplexer may sequentially connect touchelectrodes included in the third electrode group electrically to thecorresponding driving pad during the third period. The fourthsub-demultiplexer may sequentially connect touch electrodes included inthe fourth electrode group electrically to the corresponding driving padduring the fourth period.

Operations of the first demultiplexers may be controlled by same firstcontrol signals. Operations of the second demultiplexers may becontrolled by same second control signals.

The touch sensor may include the following elements: first control padslocated on the substrate for providing the first control signals to thefirst demultiplexers; and second control pads located on the substratefor providing the second control signals to the second demultiplexers.

The touch sensor may include the following elements: a first voltage padlocated on the substrate; and third demultiplexers connected between theelectrode units and the first voltage pad. The electrode units may beelectrically connected through the third multiplexers to the firstvoltage pad.

Each of the third demultiplexers may include sub-demultiplexersrespectively electrically connected to different electrode groups.

The touch sensor may include the following elements: a second voltagepad located on the substrate; and fourth demultiplexers connectedbetween the electrode units and the second voltage pad. The electrodeunits may be electrically connected through the fourth demultiplexers tothe second voltage pad.

Each of the fourth demultiplexers may include sub-demultiplexersrespectively electrically connected to different electrode groups.

The first voltage pad may provide a first voltage to the thirddemultiplexers. The second voltage pad may provide a second voltage tothe fourth demultiplexers. A voltage value of the first voltage may behigher than a voltage value of the second voltage.

Operations of the third demultiplexers may be controlled by same thirdcontrol signals. Operations of the fourth demultiplexers may becontrolled by same fourth control signals.

The touch sensor may include the following elements: third control padslocated on the substrate for providing the third control signals to thethird demultiplexers; and fourth control pads located on the substratefor providing the fourth control signals to the fourth demultiplexers.

The touch sensor may include the following elements: a connecting memberelectrically connected to the driving pads; and a touch driving unit forsupplying a driving signal to the driving pads through the connectingmember.

An embodiment may be related to a method for driving a touch sensor.

The method may include the following steps: sequentially supplying adriving signal to touch electrodes included in first electrode groupsduring a first period; subsequently, sequentially supplying the drivingsignal to touch electrodes included in second electrode groups during asecond period; subsequently, sequentially supplying the driving signalto touch electrodes included in third electrode groups during a thirdperiod; and subsequently, sequentially supplying the driving signal totouch electrodes included in fourth electrode groups during a fourthperiod. All touch electrodes in all of the first electrode groups, thesecond electrode groups, the third electrode groups, and the fourthelectrode groups except touch electrodes being currently supplied withthe driving signal may be supplied with at least one of a first voltageand a second voltage.

The first electrode groups and the third electrode groups may i bedisposed along a first direction.

The second electrode groups and the fourth electrode groups may bedisposed along the first direction.

The first electrode groups and the second electrode groups may bealternately disposed along a second direction different from the firstdirection. The third electrode groups and the fourth electrode groupsmay be alternately disposed along the second direction.

The first electrode groups and the third electrode groups may bedisposed in odd-numbered columns. The second electrode groups and thefourth electrode groups may be disposed in even-numbered columns.

During each period, some electrodes not being currently supplied withthe driving signal may be supplied with the first voltage, and otherelectrodes not being currently supplied with the driving signal may besupplied with the second voltage.

A voltage value of the first voltage may be higher than a voltage valueof the second voltage.

An embodiment may be related to a display device. The display device mayinclude the following elements: a substrate including a first region anda second region; pixels located on the first region; an encapsulationlayer covering the pixels; electrode units located on the encapsulationlayer and each including a plurality of electrode groups, the electrodegroups each including a plurality of touch electrodes; firstdemultiplexers located on the second region, each including a pluralityof sub-demultiplexers, and each being electrically connected to acorresponding one of the electrode units, each of the sub-demultiplexersof a first demultiplexer being electrically connected to a correspondingone of the electrode groups of a corresponding electrode unit; drivingpads located on the second region; and second demultiplexers located onthe second region and connected between the first demultiplexers and thedriving pads. The driving pads may be electrically connected through thesecond demultiplexers to the first demultiplexers.

The display device may include a display driver located on the secondregion for driving the pixels.

The display driver may be located between a first demultiplexer subsetof the first demultiplexers and a second demultiplexer subset of thefirst demultiplexers. The display driver may be located between a firstdemultiplexer subset of the second demultiplexers and a seconddemultiplexer subset of the second demultiplexers.

The display device may include the following elements: a connectingmember electrically connected to the driving pads; and a touch drivingunit for supplying a driving signal to the driving pads through theconnecting member.

The display device may include the following elements: a first voltagepad located on the second region; and third demultiplexers located onthe second region and connected between the electrode units and thefirst voltage pad. The electrode units may be electrically connectedthrough the third demultiplexers to the first voltage pad.

The display device may include the following elements: a second voltagepad located on the second region; and fourth demultiplexers located onthe second region and connected between the electrode units and thesecond voltage pad. The electrode units may be electrically connectedthrough the fourth demultiplexers to the second voltage pad.

The first voltage pad may provide a first voltage to the thirddemultiplexers. The second voltage pad may provide a second voltage tothe fourth demultiplexers. A voltage value of the first voltage may behigher than a voltage value higher of second voltage.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a view (e.g. plan view) illustrating a touch sensor accordingto an embodiment, and FIG. 1B is a view illustrating a touch sensor witha touch driving unit according to an embodiment.

FIG. 2 is a view (e.g., plan view) illustrating electrode units anddemultiplexers according to an embodiment.

FIG. 3 is a view illustrating a circuit configuration of a firstdemultiplexer and a second demultiplexer according to an embodiment.

FIG. 4 is a view illustrating signals provided in a driving method ofthe touch sensor according to an embodiment.

FIG. 5A, FIG. 5B, FIG. 5C, FIG. 6A, FIG. 6B, FIG. 6C, FIG. 7A, FIG. 7B,FIG. 7C, FIG. 8A, FIG. 8B, and FIG. 8C are views (e.g., plan views)illustrating activated touch electrodes for different driving periods.

FIG. 9 is a view (e.g., plan view) illustrating third demultiplexers andfourth demultiplexers according to an embodiment.

FIG. 10 is a view illustrating a circuit configuration of a thirddemultiplexer and a fourth demultiplexer according to an embodiment.

FIG. 11 is a view (e.g., plan view) illustrating a display deviceaccording to an embodiment.

FIG. 12 is a view (e.g., plan view and/or block diagram) illustrating adisplay driver and pixels of a display device according to anembodiment.

FIG. 13 is a view illustrating an embodiment of the pixel shown in FIG.12 .

FIG. 14 is a view (e.g., plan view) illustrating a display deviceaccording to an embodiment.

FIG. 15A and FIG. 15B are cross-sectional views taken along line A-A′ ofFIG. 14 according to one or more embodiments, and FIG. 15C is across-sectional view taken along line B-B′ of FIG. 14 according to anembodiment.

FIG. 16A is a view (e.g., plan view) illustrating a display deviceaccording to an embodiment.

FIG. 16B is a view illustrating a display device according to anembodiment.

DETAILED DESCRIPTION

Example embodiments are described in conjunction with the accompanyingdrawings. The embodiments may be implemented into different forms. Theseembodiments are provided for illustrative purposes.

Although the terms “first”, “second”, etc. may be used herein todescribe various elements, these elements, should not be limited bythese terms. These terms may be used to distinguish one element fromanother element. Thus, a first element discussed below may be termed asecond element without departing from teachings of one or moreembodiments. The description of an element as a “first” element may notrequire or imply the presence of a second element or other elements. Theterms “first”, “second”, etc. may also be used herein to differentiatedifferent categories or sets of elements. For conciseness, the terms“first”, “second”, etc. may represent “first-category (or first-set)”,“second-category (or second-set)”, etc., respectively.

In the specification, when an element is referred to as being“connected” or “coupled” to another element, it can be directlyconnected or coupled to the another element or be indirectly connectedor coupled (e.g., electrically connected) to the another element throughone or more intervening elements. A “signal” may mean one or more copiesof the signal. Like reference numerals may refer to like elements.

FIG. 1A is a view illustrating a touch sensor 1 according to anembodiment, and FIG. 1B is a view illustrating a touch sensor includinga touch driving unit according to an embodiment.

Referring to FIG. 1A, the touch sensor 1 may include a substrate 10,electrode units 100, a demultiplexer 200, and driving pads 310.

The substrate 10 may include a first region A1 and a second region A2.The first region A1 is a region in which the electrode units 100 arelocated, and may be referred to as a touch active region.

In an embodiment, the remaining region located at the periphery of thefirst region A1 may be referred to as a touch non-active region, and thesecond region A2 may be defined as at least a partial region of thetouch non-active region.

The second region A2 is a region in which the demultiplexer 200 and thedriving pads 310 are located, and may be located at one side of thefirst region A1.

The substrate 10 may be made of an insulative/insulating material suchas glass or resin. In an embodiment, the substrate 10 may be made of amaterial having flexibility to be bendable or foldable. The substrate 10may have a single- or multi-layered structure.

For example, the substrate 10 may include at least one of polystyrene,polyvinyl alcohol, polymethyl methacrylate, polyethersulfone,polyacrylate, polyetherimide, polyethylene naphthalate, polyethyleneterephthalate, polyphenylene sulfide, polyarylate, polyimide,polycarbonate, triacetate cellulose, cellulose acetate propionate, andpolyurethane.

In an embodiment, the substrate 10 may be made of fiber glass reinforcedplastic (FRP), or the like.

The electrode units 100 may be located on the first region A1 of thesubstrate 10, and each of the electrode units 100 may include aplurality of touch electrodes 110.

The touch electrodes 110 may be activated through driving signalssupplied from the demultiplexer 200.

In addition, the touch electrodes 110 may include a conductive material.For example, the conductive material may include a metal or an alloy.Examples of the metal may include gold (Au), silver (Ag), aluminum (Al),molybdenum (Mo), chromium (Cr), titanium (Ti), nickel (Ni), neodymium(Nd), copper (Cu), platinum (Pt), and the like.

In an embodiment, the touch electrodes 110 may be made of a transparentconductive material. Examples of the transparent conductive material mayinclude silver nanowire (AgNW), indium tin oxide (ITO), indium zincoxide (IZO), antimony zinc oxide (AZO), indium tin zinc oxide (ITZO),zinc oxide (ZnO), tin oxide (SnO₂), carbon nano tube, graphene, and thelike. The touch electrodes 110 may have a single- or multi-layeredstructure.

The demultiplexer 200 may be located on the second region A2 of thesubstrate 10. In an embodiment, the demultiplexer 200 may selectivelyconnect the touch electrodes 110 electrically to the driving pads 310.

Accordingly, the demultiplexer 200 can time-divisionally supply drivingsignals applied through the driving pads 310 to the touch electrodes110.

The driving pads 310 may be located on the second region A2 of thesubstrate 10. In an embodiment, the driving pads 310 may receive drivingsignals supplied from an external source.

For example, driving signals may be supplied to the driving pads througha separate driving device (not shown) in a test process before productshipment.

In a typical touch sensor, the number of driving pads may need to beequal to the number of touch electrodes in order to supply drivingsignals to all the touch electrodes. In contrast, in an embodiment, thedemultiplexer 200 is provided, so that the number of driving pads 310can be significantly less than the touch electrodes. Accordingly, thetotal area of dead spaces (i.e., areas not used for displaying images orreceiving touches) can be effectively minimized.

Referring to FIG. 1B, the touch sensor 1 may include a connecting member450 and a touch driving unit 460.

The connecting member 450 may be attached to and/or electricallyconnected to the driving pads 310, and the touch driving unit 460 maysupply driving signals to the driving pads 310 through the connectingmember 450. In an embodiment, the touch driving unit 460 may be mountedon the connecting member 450.

In an embodiment, the touch sensor 1 may be driven using a separatedriving device (not shown) in a test process before product shipment,and the touch driving unit 460 may be additionally installed after thetest process to drive the touch sensor 1.

In an embodiment, the connecting member 450 may be implemented as aflexible printed circuit board (FPCB), and the touch driving unit 460may be implemented as an integrated circuit (IC).

The above-described touch electrodes 110 may be spaced apart from eachother. The touch electrodes 110 may output, to the touch driving unit460, one or more sensing signals indicating a change in capacitance.

For example, the touch driving unit 460 may receive a sensing signaloutput from the touch electrodes 110 through the demultiplexer 200 andthe driving pads 310.

When a touch is applied to the touch sensor 1, the self-capacitance oftouch electrodes 110 related to the touch is changed. Thus, the touchdriving unit 460 can detect a touch position using a sensing signaloutput from the touch electrodes 110.

FIG. 2 is a view illustrating electrode units and demultiplexersaccording to an embodiment.

Referring to FIG. 2 , each of the electrode units 100 may include aplurality of electrode groups.

For example, each of the electrode units 100 may include a firstelectrode group 101, a second electrode group 102, a third electrodegroup 103, and a fourth electrode group 104.

The electrode groups 101, 102, 103, and 104 may each include a pluralityof touch electrodes 110.

In an embodiment, the first electrode group 101 and the third electrodegroup 103 may be disposed immediately adjacent to each other along afirst direction (e.g., a Y-axis direction), and the second electrodegroup 102 and the fourth electrode group 104 may be disposed immediatelyadjacent to each other along the first direction.

In an embodiment, the first electrode group 101 and the second electrodegroup 102 may be disposed adjacent to each other along a seconddirection (e.g., an X-axis direction) different from the firstdirection, and the third electrode group 103 and the fourth electrodegroup 104 may be disposed adjacent to each other along the seconddirection.

In an embodiment, the first electrode group 101 and the third electrodegroup 103 may be disposed in an ith (i is a natural number of 1 or more)column, and the second electrode group 102 and the fourth electrodegroup 104 may be disposed in an (i+l)th column.

In an embodiment, a plurality of first electrode groups 101 and aplurality of third electrode groups 103 may be disposed in odd-numberedcolumns, and a plurality of second electrode groups 102 and a pluralityof fourth electrode groups 104 may be disposed in even-numbered columns.

In an embodiment, the demultiplexer 200 may include a plurality of firstdemultiplexers 210 and a plurality of second demultiplexers 220.

The first demultiplexers 210 may be connected to the electrode units100, respectively. In an embodiment, the first demultiplexers 210 mayeach include a plurality of sub-demultiplexers 211, 212, 213, and 214respectively electrically connected to the electrode groups 101, 102,103, and 104 of a corresponding electrode unit 100.

For example, a demultiplexer 210 may include a first sub-demultiplexer211, a second sub-demultiplexer 212, a third sub-demultiplexer 213, anda fourth sub-demultiplexer 214.

The first sub-demultiplexer 211 may be connected between a correspondingfirst electrode group 101 and a corresponding second demultiplexer 220.In an embodiment, the first sub-demultiplexer 211 may selectivelyconnect touch electrodes 110 of the corresponding first electrode group101 electrically to the corresponding second demultiplexer 220.

The second sub-demultiplexer 212 may be connected between acorresponding second electrode group 102 and the corresponding seconddemultiplexer 220. In an embodiment, the second sub-demultiplexer 212may selectively connect touch electrodes 110 of the corresponding secondelectrode group 102 electrically to the corresponding seconddemultiplexer 220.

The third sub-demultiplexer 213 may be connected between a correspondingthird electrode group 103 and the corresponding second demultiplexer220. In an embodiment, the third sub-demultiplexer 213 may selectivelyconnect touch electrodes 110 of the corresponding third electrode group103 electrically to the corresponding second demultiplexer 220.

The fourth sub-demultiplexer 214 may be connected between acorresponding fourth electrode group 104 and the corresponding seconddemultiplexer 220. In an embodiment, the fourth sub-demultiplexer 214may selectively connect touch electrodes 110 of the corresponding fourthelectrode group 104 electrically to the corresponding seconddemultiplexer 220.

The second demultiplexers 220 may be connected between the firstdemultiplexers 210 and driving pads 310.

A second demultiplexer 220 may selectively connect thesub-demultiplexers 211, 212, 213, and 214 of a corresponding firstdemultiplexer 210 electrically to a corresponding driving pad 310.

For example, each of the second demultiplexers 220 may electricallyconnect a corresponding first sub-demultiplexer 211 to a correspondingdriving pad 310 during a first period, (subsequently) electricallyconnect a corresponding second sub-demultiplexer 212 to the driving pad310 during a second period, (subsequently) electrically connect acorresponding third sub-demultiplexer 213 to the driving pad 310 duringa third period, and (subsequently) electrically connect a correspondingfourth sub-demultiplexer 214 to the driving pad 310 during a fourthperiod.

In an embodiment, each of the first sub-demultiplexers 211 maysequentially connect the touch electrodes 110 included in thecorresponding first electrode group 101 electrically to the driving pad310 during the first period, and (subsequently) each of the secondsub-demultiplexers 212 may sequentially connect the touch electrodes 110included in the corresponding second electrode group 102 electrically tothe driving pad 310 during the second period.

In an embodiment, (subsequently) each of the third sub-demultiplexers213 may sequentially connect the touch electrodes 110 included in thecorresponding third electrode group 103 electrically to the driving pad310 during the third period, and (subsequently) each of the fourthsub-demultiplexers 214 may sequentially connect the touch electrodes 110included in the corresponding fourth electrode group 104 electrically tothe driving pad 310 during the fourth period.

In an embodiment, operations of the first demultiplexers 210 may becontrolled by (copies of) the same first control signal(s) Cs1, andoperations of the second demultiplexers 220 may be controlled by (copiesof) the same second control signal(s) Cs2.

FIG. 3 is a view illustrating a circuit configuration of a firstdemultiplexer and a second demultiplexer according to an embodiment. Anelectrode unit 100, a first demultiplexer 210, and a seconddemultiplexer 220, which are related to one driving pad 310, areillustrated in FIG. 3 .

Referring to FIG. 3 , a first sub-demultiplexer 211 may include aplurality of transistors T11, T12, to T1 n.

The transistors T11 to T1 n may be connected between touch electrodes110 of a first electrode group 101 and the second demultiplexer 220.

The transistors T11 to T1 n may be provided in the same number as thetouch electrodes 110 included in the first electrode group 101. In anembodiment, n transistors T11 to T1 n may be connected one-to-one to ntouch electrodes 110 included in the first electrode group 101, whereinn is a natural number.

For example, first electrodes of the transistors T11 to T1 n may beconnected to the touch electrodes 110 of the first electrode group 101,respectively, and second electrodes of the transistors T11 to T1 n maybe commonly connected to a first transistor M1 of the seconddemultiplexer 220.

In an embodiment, gate electrodes of the transistors T11 to T1 n may beconnected to first control pads 321, respectively.

Accordingly, the transistors T11 to T1 n can be turned on correspondingto electrode selection signals Es1, Es2, to Esn supplied from the firstcontrol pads 321.

A second sub-demultiplexer 212 may include a plurality of transistorsT21, T22, to T2 n.

The transistors T21 to T2 n may be connected between touch electrodes110 of a second electrode group 102 and the second demultiplexer 220.

The transistors T21 to T2 n may be provided in the same number as thetouch electrodes 110 included in the second electrode group 102. In anembodiment, n transistors T21 to T2 n may be connected one-to-one to ntouch electrodes 110 included in the second electrode group 102.

For example, first electrodes of the transistors T21 to T2 n may beconnected to the touch electrodes 110 of the second electrode group 102,respectively, and second electrodes of the transistors T21 to T2 n maybe commonly connected to a second transistor M2 of the seconddemultiplexer 220.

In an embodiment, gate electrodes of the transistors T21 to T2 n may beconnected to the first control pads 321, respectively.

Accordingly, the transistors T21 to T2 n can be turned on correspondingto the electrode selection signals Es1 to Esn supplied from the firstcontrol pads 321.

A third sub-demultiplexer 213 may include a plurality of transistorsT31, T32, to T3 n.

The transistors T31 to T3 n may be connected between touch electrodes110 of a third electrode group 103 and the second demultiplexer 220.

The transistors T31 to T3 n may be provided in the same number as thetouch electrodes 110 included in the third electrode group 103. In anembodiment, n transistors T31 to T3 n may be connected one-to-one to ntouch electrodes 110 included in the third electrode group 103.

For example, first electrodes of the transistors T31 to T3 n may beconnected to the touch electrodes 110 of the third electrode group 103,respectively, and second electrodes of the transistors T31 to T3 n maybe commonly connected to a third transistor M3 of the seconddemultiplexer 220.

In an embodiment, gate electrodes of the transistors T31 to T3 n may beconnected to the first control pads 321, respectively.

Accordingly, the transistors T31 to T3 n can be turned on correspondingto the electrode selection signals Es1 to Esn supplied from the firstcontrol pads 321.

A fourth sub-demultiplexer 214 may include a plurality of transistorsT41, T42, to T4 n.

The transistors T41 to T4 n may be connected between touch electrodes110 of a fourth electrode group 104 and the second demultiplexer 220.

The transistors T41 to T4 n may be provided in the same number as thetouch electrodes 110 included in the fourth electrode group 104. In anembodiment, n transistors T41 to T4 n may be connected one-to-one to ntouch electrodes 110 included in the fourth electrode group 104.

For example, first electrodes of the transistors T41 to T4 n may beconnected to the touch electrodes 110 of the fourth electrode group 104,respectively, and second electrodes of the transistors T41 to T4 n maybe commonly connected to a fourth transistor M4 of the seconddemultiplexer 220.

In an embodiment, gate electrodes of the transistors T41 to T4 n may beconnected to the first control pads 321, respectively.

Accordingly, the transistors T41 to T4 n can be turned on correspondingto the electrode selection signals Es1 to Esn supplied from the firstcontrol pads 321.

The second demultiplexer 220 may include a plurality of transistors M1,M2, M3, and M4.

The transistors M1 to M4 may be connected between the driving pad 310and the sub-demultiplexers 211, 212, 213, and 214 of the firstdemultiplexer 210.

For example, a first electrode of the first transistor M1 may becommonly connected to the transistors T11 to T1 n of the firstsub-demultiplexer 211, and a second electrode of the first transistor M1may be connected to the driving pad 310.

In an embodiment, a first electrode of the second transistor M2 may becommonly connected to the transistors T21 to T2 n of the secondsub-multiplexer 212, and a second electrode of the second transistor M2may be connected to driving pad 310.

In an embodiment, a first electrode of the third transistor M3 may becommonly connected to the transistors T31 to T3 n of the thirdsub-demultiplexer 213, and a second electrode of the third transistor M3may be connected to the driving pad 310.

In an embodiment, a first electrode of the fourth transistor M4 may becommonly connected to the transistors T41 to T4 n of the fourthdemultiplexer 214, and a second electrode of the fourth transistor M2may be connected to the driving pad 310.

Gate electrodes of the first to fourth transistors M1 to M4 may beconnected to second control pads 322, respectively.

Accordingly, the first to fourth transistors M1 to M4 can be turned oncorresponding to group selection signals Gs1, Gs2, Gs3, and Gsn suppliedfrom the second control pads 322.

The first control pads 321 may be located on the second region A2 of thesubstrate 10. In an embodiment, the first control pads 321 may receivefirst control signals Cs1 supplied from an external source. For example,the first control signals Cs1 may include the electrode selectionsignals Es1 to Esn.

The second control pads 322 may be located on the second region A2 ofthe substrate 10. In an embodiment, the second control pads 322 mayreceive second control signals Cs2 supplied from the external source.For example, the second control signals Cs2 may include the groupselection signals Gs1 to Gsn.

In an embodiment, the control signals Cs1 and Cs2 may be supplied to thecontrol pads 321 and 322 through a separate driving device (not shown)in a test process before product shipment.

In an embodiment, the connecting member 450 may be attached to thecontrol pads 321 and 322 after the test process, and the touch drivingunit 460 may supply the control signals Cs1 and Cs2 to the control pads321 and 322 through the connecting member 450.

FIG. 4 is a view illustrating signals used in a driving method of thetouch sensor according to an embodiment. FIGS. 5A to 8C are viewsillustrating activated touch electrodes for different driving periods.In particular, in FIGS. 5A to 8C, touch electrodes 110 supplied with(copies of) a signal Ds are indicated by black.

Hereinafter, a driving method of the touch sensor 1 according to anembodiment will be described with reference to FIGS. 3, 4, and 5A to 8C.

Referring to FIG. 4 , the driving method of the touch sensor 1 accordingto the embodiment may be performed during a driving period divided intoa first period P1, a second period P2, a third period P3, and a fourthperiod P4.

First, a driving signal Ds may be continuously supplied to the drivingpad 310 during the driving period P1 to P4 of the touch sensor 1.

A first group selection signal Gs1 may be supplied to the seconddemultiplexer 220 during the first period P1.

Therefore, the first transistor M1 of the second demultiplexer 220 maybe turned on, and accordingly, the driving signal Ds may be supplied tothe first sub-demultiplexer 211.

In an embodiment, as the electrode selection signals Es1 to Esn aresequentially supplied during the first period P1, the transistors T11 toT1 n included in the first sub-demultiplexer 211 may also besequentially turned on.

Therefore, the driving signal Ds may be sequentially supplied to thetouch electrodes 110 included in the first electrode group 101.

In an embodiment, as shown in FIGS. 5A to 5C, the touch electrodes 110included in the first electrode group 101 may be sequentially suppliedwith the driving signal DS to be activated.

In an embodiment, a second group selection signal Gs2 may be supplied tothe second demultiplexer 220 during the second period P2.

Therefore, the second transistor M2 of the second demultiplexer 220 maybe turned on, and accordingly, the driving signal Ds may be supplied tothe second sub-demultiplexer 212.

In an embodiment, as the electrode selection signals Es1 to Esn aresequentially supplied during the second period P2, the transistors T21to T2 n included in the second sub-demultiplexer 212 may also besequentially turned on.

Therefore, the driving signal Ds may be sequentially supplied to thetouch electrodes 110 included in the second electrode group 102.

As shown in FIGS. 6A to 6C, the touch electrodes 110 included in thesecond electrode group 102 may be sequentially supplied with the drivingsignal Ds to be activated.

In an embodiment, a third group selection signal Gs3 may be supplied tothe second demultiplexer 220 during the third period P3.

Therefore, the third transistor M3 of the second demultiplexer 220 maybe turned on, and accordingly, the driving signal Ds may be supplied tothe third sub-demultiplexer 213.

In an embodiment, as the electrode selection signals Es1 to Esn aresequentially supplied during the third period P3, the transistors T31 toT3 n included in the third sub-demultiplexer 213 may also besequentially turned on.

Therefore, the driving signal Ds may be sequentially supplied to thetouch electrodes 110 included in the third electrode group 103.

In an embodiment, as shown in FIGS. 7A to 7C, the touch electrodes 110included in the third electrode group 103 may be sequentially suppliedwith the driving signal Ds to be activated.

In an embodiment, a fourth group selection signal Gs4 may be supplied tothe second demultiplexer 220 during the fourth period P4.

Therefore, the fourth transistor M4 of the second demultiplexer 220 maybe turned on, and accordingly, the driving signal Ds may be supplied tothe fourth sub-demultiplexer 214.

In an embodiment, as the electrode selection signals Est to Esn aresequentially supplied during the fourth period P4, the transistors T41to T4 n included in the fourth sub-demultiplexer 214 may also besequentially turned on.

Therefore, the driving signal Ds may be sequentially supplied to thetouch electrodes 110 included in the fourth electrode group 104.

In an embodiment, as shown in FIGS. 8A to 8C, the touch electrodes 110included in the fourth electrode group 104 may be sequentially suppliedwith the driving signal Ds to be activated.

FIG. 9 is a view illustrating third demultiplexers and fourthdemultiplexers according to an embodiment.

Referring to FIG. 9 , the demultiplexer 200 may further include thirddemultiplexers 230 and fourth demultiplexers 240.

The third demultiplexers 230 may be connected to the electrode units100, respectively. In an embodiment, a third demultiplexer 230 may eachinclude a plurality of sub-demultiplexers 231, 232, 233, and 234respectively connected to the electrode groups 101, 102, 103, and 104 ofa corresponding electrode unit 100.

For example, a third demultiplexer 230 may include a firstsub-demultiplexer 231, a second sub-demultiplexer 232, a thirdsub-demultiplexer 233, and a fourth sub-demultiplexer 234.

The first sub-demultiplexer 231 may be connected to a first electrodegroup 101, and be supplied with a first voltage V1. In an embodiment,the first sub-demultiplexer 231 may selectively supply the first voltageV1 supplied thereto to touch electrodes 110 included in the firstelectrode group 101.

The second sub-demultiplexer 232 may be connected to a second electrodegroup 102, and be supplied with the first voltage V1. In an embodiment,the second sub-demultiplexer 232 may selectively supply the firstvoltage V1 supplied thereto to touch electrodes 110 included in thesecond electrode group 102.

The third sub-demultiplexer 233 may be connected to a third electrodegroup 103, and be supplied with the first voltage V1. In an embodiment,the third sub-demultiplexer 233 may selectively supply the first voltageV1 supplied thereto to touch electrodes 110 included in the thirdelectrode group 103.

The fourth sub-demultiplexer 234 may be connected to a fourth electrodegroup 140, and be supplied with the first voltage V1. In an embodiment,the fourth sub-demultiplexer 234 may selectively supply the firstvoltage V1 supplied thereto to touch electrodes 110 included in thefourth electrode group 104.

The fourth demultiplexers 240 may be connected to the electrode units100, respectively. In an embodiment, the fourth demultiplexers 240 mayeach include a plurality of demultiplexers 241, 242, 243, and 244respectively connected to the electrode groups 101, 102, 103, and 104 ofa corresponding electrode unit 100.

For example, each of the fourth demultiplexers 240 may include a firstsub-demultiplexer 241, a second sub-demultiplexer 242, a thirdsub-demultiplexer 243, and a fourth sub-demultiplexer 244.

The first sub-demultiplexer 241 may be connected to the first electrodegroup 101, and be supplied with a second voltage V2. In an embodiment,the first sub-demultiplexer 241 may selectively supply the secondvoltage V2 supplied thereto to the touch electrodes 110 included in thefirst electrode group 101.

The second sub-demultiplexer 242 may be connected to the secondelectrode group 102, and be supplied with the second voltage V2. In anembodiment, the second sub-demultiplexer 242 may selectively supply thesecond voltage V2 supplied thereto to the touch electrodes 110 includedin the second electrode group 102.

The third sub-demultiplexer 243 may be connected to the third electrodegroup 103, and be supplied with the second voltage V2. In an embodiment,the third sub-demultiplexer 243 may selectively supply the secondvoltage V2 supplied thereto to the touch electrodes 110 included in thethird electrode group 103.

The fourth sub-demultiplexer 244 may be connected to the fourthelectrode group 104, and be supplied with the second voltage V2. In anembodiment, the fourth sub-demultiplexer 244 may selectively supply thesecond voltage V2 supplied thereto to the touch electrodes 110 includedin the fourth electrode group 104.

Here, a voltage value of the first voltage V1 may be higher than avoltage value of the second voltage V2. For example, the second voltageV2 may be set to a ground voltage.

In an embodiment, operations of the third demultiplexers 230 may becontrolled by the same third control signals Cs3, and operations of thefourth demultiplexers 240 may be controlled by the same control signalsCs4.

FIG. 10 is a view illustrating a circuit configuration of a thirddemultiplexer and a fourth demultiplexer according to an embodiment. Anelectrode unit 100, a first demultiplexer 210, a second demultiplexer220, a third demultiplexer 230, and a fourth demultiplexer 240, whichare related to one driving pad 310, are illustrated in FIG. 10 .

Referring to FIG. 10 , a first sub-demultiplexer 231 of the thirddemultiplexer 230 may include a plurality of transistors A11, A12, to A1n.

The transistors A11 to A1 n may be connected between touch electrodes110 of a first electrode group 101 and a first voltage pad 331.

The transistors A11 to A1 n may be provided in the same number as thetouch electrodes 110 included in the first electrode group 101. In anembodiment, n transistors A11 to A1 n may be connected one-to-one to ntouch electrodes 110 included in the first electrode group 101.

For example, first electrodes of the transistors A11 to A1 n may beconnected to the touch electrodes 110 of the first electrode group 101,respectively, and second electrodes of the transistors A11 to A1 n maybe commonly connected to the first voltage pad 331.

In an embodiment, gate electrodes of the transistors A11 to A1 n may beconnected to third control pads 323, respectively.

Accordingly, the transistors A11 to A1 n can be turned on correspondingto electrode selection signals Ea1, Ea2, to Ean supplied from the thirdcontrol pads 323.

A second sub-demultiplexer 232 of the third demultiplexer 230 mayinclude a plurality of transistors A21, A22, to A2 n.

The transistors A21 to A2 n may be connected between touch electrodes110 of a second electrode group 102 and the first voltage pad 331.

The transistors A21 to A2 n may be provided in the same number as thetouch electrodes 110 included in the second electrode group 102. In anembodiment, n transistors A21 to A2 n may be connected one-to-one to ntouch electrodes 110 included in the second electrode group 102.

For example, first electrodes of the transistors A21 to A2 n may beconnected to the touch electrodes 110 of the second electrode group 102,respectively, and second electrodes of the transistors A21 to A2 n maybe commonly connected to the first voltage pad 331.

In an embodiment, gate electrodes of the transistors A21 to A2 n may beconnected to the third control pads 323, respectively.

Accordingly, the transistors A21 to A2 n can be turned on correspondingto the electrode selection signals Ea1 to Ean supplied from the thirdcontrol pads 323.

A third sub-demultiplexer 233 of the third demultiplexer 230 may includea plurality of transistors A31, A32, to A3 n.

The transistors A31 to A3 n may be connected between touch electrodes110 of a third electrode group 103 and the first voltage pad 331.

The transistors A31 to A3 n may be provided in the same number as thetouch electrodes 110 included in the third electrode group 103. In anembodiment, n transistors A31 to A3 n may be connected one-to-one to ntouch electrodes 110 included in the third electrode group 103.

For example, first electrodes of the transistors A31 to A3 n may beconnected to the touch electrodes 110 of the third electrode group 103,respectively, and second electrodes of the transistors A31 to A3 n maybe commonly connected to the first voltage pad 331.

In an embodiment, gate electrodes of the transistors A31 to A3 n may beconnected to the third control pads 323, respectively.

Accordingly, the transistors A31 to A3 n can be turned on correspondingto the electrode selection signals Ea1 to Ean supplied from the thirdcontrol pads 323.

A fourth sub-demultiplexer 234 of the third demultiplexer 230 mayinclude a plurality of transistors A41, A42, to A4 n.

The transistors A41 to A4 n may be connected between touch electrodes110 of a fourth electrode group 104 and the first voltage pad 331.

The transistors A41 to A4 n may be provided in the same number as thetouch electrodes 110 included in the fourth electrode group 104. In anembodiment, n transistors A41 to A4 n may be connected one-to-one to ntouch electrodes 110 included in the fourth electrode group 104.

For example, first electrodes of the transistors A41 to A4 n may beconnected to the touch electrodes 110 of the fourth electrode group 101,respectively, and second electrodes of the transistors A41 to A4 n maybe commonly connected to the first voltage pad 331.

In an embodiment, gate electrodes of the transistors A41 to A4 n may beconnected to the third control pads 323, respectively.

Accordingly, the transistors A41 to A4 n can be turned on correspondingto the electrode selection signals Ea1 to Ean supplied from the thirdcontrol pads 323.

A first sub-demultiplexer 241 of the fourth demultiplexer 240 mayinclude a plurality of transistors B11, B12, to B1 n.

The transistors B11 to B1 n may be connected between the touchelectrodes 110 of the first electrode group 101 and a second voltage pad332.

The transistors B11 to B1 n may be provided in the same number as thetouch electrodes 110 included in the first electrode group 101. In anembodiment, n transistors B11 to B1 n may be connected one-to-one to ntouch electrodes 110 included in the first electrode group 101.

For example, first electrodes of the transistors B11 to B1 n may beconnected to the touch electrodes 110 of the first electrode group 101,respectively, and second electrodes of the transistors B11 to B1 n maybe commonly connected to the second voltage pad 332.

In an embodiment, gate electrodes of the transistors B11 to B1 n may beconnected to fourth control pads 324, respectively.

Accordingly, the transistors B11 to B1 n can be turned on correspondingto electrode selection signals Eb1, Eb2, to Ebn supplied from the fourthcontrol pads 324.

A second sub-demultiplexer 242 of the fourth demultiplexer 240 mayinclude a plurality of transistors B21, B22, to B2 n.

The transistors B21 to B2 n may be connected between the touchelectrodes 110 of the second electrode group 102 and the second voltagepad 332.

The transistors B21 to B2 n may be provided in the same number as thetouch electrodes 110 included in the second electrode group 102. In anembodiment, n transistors B21 to B2 n may be connected one-to-one to ntouch electrodes 110 include in the second electrode group 102.

For example, first electrodes of the transistors B21 to B2 n may beconnected to the touch electrodes 110 of the second group 102,respectively, and second electrodes of the transistors B21 to B2 n maybe commonly connected to the second voltage pad 332.

In an embodiment, gate electrodes of the transistors B21 to B2 n may beconnected to the fourth control pads 324, respectively.

Accordingly, the transistors B21 to B2 n can be turned on correspondingto the electrode selection signals Eb1 to Ebn supplied from the fourthcontrol pads 324.

A third sub-demultiplexer 243 of the fourth demultiplexer 240 mayinclude a plurality of transistors B31, B32, to B3 n.

The transistors B31 to B3 n may be connected between the touchelectrodes 110 of the third electrode group 103 and the second voltagepad 332.

The transistors B31 to B3 n may be provided in the same number as thetouch electrodes 110 included in the third electrode group 103. In anembodiment, n transistors B31 to B3 n may be connected one-to-one to ntouch electrodes 110 included in the third electrode group 103.

For example, first electrodes of the transistors B31 to B3 n may beconnected to the touch electrodes 110 of the third electrode group 103,respectively, and second electrodes of the transistors B31 to B3 n maybe commonly connected to the second voltage pad 332.

In an embodiment, gate electrodes of the transistors B31 to B3 n may beconnected to the fourth control pads 324, respectively.

Accordingly, the transistors B31 to B3 n can be turned on correspondingto the electrode selection signals Eb1 to Ebn supplied from the fourthcontrol pads 324.

A fourth sub-demultiplexer 244 of the fourth demultiplexer 240 mayinclude a plurality of transistors B41, B42, to B4 n.

The transistors B41 to B4 n may be connected between the touchelectrodes 110 of the fourth electrode group 104 and the second voltagepad 332.

The transistors B41 to B4 n may be provided in the same number as thetouch electrodes 110 included in the fourth electrode group 104. In anembodiment, n transistors B41 to B4 n may be connected one-to-one to ntouch electrodes 110 included in the fourth electrode group 104.

For example, first electrodes of the transistors B41 to B4 n may beconnected to the touch electrodes 110 of the fourth electrode group 104,respectively, and second electrodes of the transistors B41 to B4 n maybe commonly connected to the second voltage pad 332.

In an embodiment, gate electrodes of the transistors B41 to B4 n may beconnected to the fourth control pads 324, respectively.

Accordingly, the transistors B41 to B4 n can be turned on correspondingto the electrode selection signals Eb1 to Ebn supplied from the fourthcontrol pads 324.

The third control pads 323 may be located on the second region A2 of thesubstrate 10. In an embodiment, the third control pads 323 may receivethird control signals Cs3 supplied from the outside. For example, thethird control signals Cs3 may include the electrode selection signalsEa1 to Ean.

The fourth control pads 324 may be located on the second region A2 ofthe substrate 10. In an embodiment, the fourth control pads 324 mayreceive fourth control signals Cs4 supplied from the outside. Forexample, the fourth control signals Cs4 may include the electrodeselection signals Eb1 to Ebn.

In an embodiment, the control signals Cs3 and Cs4 may be supplied to thecontrol pads 323 and 324 through a separate driving device (not shown)in a test process before product shipment.

In an embodiment, the connecting member 450 may be attached to thecontrol pads 323 and 324 after the test process, and the touch drivingunit 460 may supply the control signals Cs3 and Cs4 to the control pads323 and 324 through the connecting member 450.

According to the above-described configuration, the third demultiplexers230 may supply the first voltage V1 to some touch electrodes 110 that donot receive the driving signal Ds during the driving period, and thefourth demultiplexers 240 may supply the second voltage V2 to othertouch electrodes 110 that do not receive the driving signal Ds duringthe driving period.

For example, all the touch electrodes 110 except touch electrodes 110currently supplied with the driving signal Ds may be supplied with thefirst voltage V1 or the second voltage V2 during the driving period.

In an embodiment, all the touch electrodes 110 except touch electrodes110 currently supplied with the driving signal Ds may be all set to afloating state. In an embodiment, all the touch electrodes 110 excepttouch electrodes 110 currently supplied with the driving signal Ds maybe set to a specific voltage, so that interference between touch signalscan be minimized, thereby improving touch sensitivity.

For example, in relation to FIG. 4 described above, during each periodP1, P2, P3, or P4, touch electrodes 110 except the touch electrodes 110currently supplied with the driving signal Ds may be supplied with atleast one of the first voltage V1 and the second voltage V2.

In an embodiment, some touch electrodes 100 not currently receiving thedriving signal Ds may be supplied with the first voltage V1, and othertouch electrodes 110 not currently receiving the driving signal Ds maybe supplied with the second voltage V2.

FIG. 11 is a view illustrating a display device 2 according to anembodiment.

Referring to FIG. 11 , the display device 2 may include a substrate 10,pixels 410, an encapsulation layer 420, and a display driver 430.

The substrate 10 may include a first region A1 and a second region A2.The first region A1 is a region in which the pixels 410 are located, andmay be referred to as a display region in which an image is displayed.The display region may correspond to the touch active region describedabove.

In an embodiment, the remaining region located at the periphery of thefirst region A1 may be referred to as a non-display region, and thesecond region A2 may be defined as a partial region in the non-displayregion.

The second region A2 is a region in which the display driver 430 islocated, and may be located at one side of the first region A1.

In an embodiment, the substrate 10 may further include a bending regionBA located between the first region A1 and the second region A2.

The bending region BA means a portion at which the substrate 10 is bent,and the second region A2 may be located adjacent to a rear surface ofthe substrate 10 due to the bending region BA.

The pixels 410 may be located on the first region A1 of the substrate10, and each of the pixels 410 emits light of a specific color, so thata predetermined image can be provided to a user.

The encapsulation layer 420 may be formed on the pixels 410, to coverand protect the pixels 410.

In an embodiment, the encapsulation layer 420 blocks the pixels 410 frombeing exposed to moisture, oxygen, etc., thereby preventing damage ofthe pixels 410.

In an embodiment, the encapsulation layer 420 may be formed in astructure including a plurality of stacked layers. For example, theencapsulation layer 420 may include at least one organic layer (notshown) and at least one inorganic layer (not shown).

When the encapsulation layer 420 is formed in a multi-layered structure,organic and inorganic layers may be alternately stacked.

The display driver 430 may be located on the second area A2 of thesubstrate 10. The display driver 430 may control emission operations ofthe pixels 410.

FIG. 12 is a view illustrating a display driver and pixels according toan embodiment.

Referring to FIG. 12 , the pixels 410 may be connected to data lines D1,D2, D3, D4 to Dq and the scan lines S1, S2, S3, S4 to Sp-1, Sp. Forexample, the pixels 410 may be arranged in a matrix form in intersectionportions of the data lines D1 to Dq and the scan lines S1 to Sp.

The pixels 410 may be supplied with data and scan signals through thedata lines D1 to Dq and the scan lines S1 to Sp.

In an embodiment, the pixels 410 may be connected to a first powersource ELVDD and a second power source ELVSS.

Each of the pixels 410 may include a light emitting device (e.g., anorganic light emitting diode). Each of the pixels 410 may generate lightcorresponding to a data signal by current flowing from the first powersource ELVDD to the second power source ELVSS via the light emittingdevice.

The display driver 430 may include a scan driver 431, a data driver 432,and a timing controller 435.

The scan driver 431 may supply scan signals to the scan lines S1 to Spin response to a scan driver control signal SCS. For example, the scandriver 431 may sequentially supply scan signals to the scan lines S1 toSp.

The data driver 432 may generate a data signal by receiving a datadriver control signal DCS and image data DATA, input from the timingcontroller 435.

The data driver 432 may supply the generated data signal to the datalines D1 to Dq.

If a scan signal is supplied to a specific scan line, some pixels 410connected to the specific scan line may receive a data signal suppliedfrom the data lines D1 to Dq. The some pixels 410 may emit light with aluminance corresponding to the received data signal.

The timing controller 435 may generate control signals for controllingthe scan driver 431 and the data driver 432.

For example, the control signals may include the scan driver controlsignal SCS for controlling the scan driver 431 and the data drivercontrol signal DCS for controlling the data driver 432.

In an embodiment, the timing controller 435 may generate the scan drivercontrol signal SCS and the data driver control signal DCS, using anexternal input signal.

In an embodiment, the timing controller 435 may supply the scan drivercontrol signal SCS to the scan driver 431, and supply the data drivercontrol signal DCS to the data driver 432.

The timing controller 435 may convert image data input from the outsideinto image data DATA suitable for specifications of the data driver 432and supply the image data DATA to the data driver 432.

The scan driver 431, the data driver 432, and the timing controller 435may be formed in one integrated circuit (IC).

FIG. 13 is a view illustrating an embodiment of the pixel shown in FIG.12 . In particular, for convenience of description, a pixel 410connected to a pth scan line Sp and a qth data line Dq is illustrated inFIG. 13 .

First, referring to FIG. 13 , the pixel 410 includes an organic lightemitting diode OLED, and a pixel circuit PC coupled to the qth data lineDq and the pth scan line Sp to control the organic light emitting diodeOLED.

An anode electrode of the organic light emitting diode OLED may beconnected to the pixel circuit PC, and a cathode electrode of theorganic light emitting diode OLED may be connected to the second powersource ELVSS.

The organic light emitting diode OLED may generate light with apredetermined luminance, corresponding to current supplied from thepixel circuit PC.

The pixel circuit PC may store a data signal supplied to the qth dataline Dq when a scan signal is supplied to the pth scan line Sp. Thepixel circuit PC may control the amount of current supplied to theorganic light emitting diode OLED, corresponding to the stored datasignal.

For example, the pixel circuit PC may include a first transistor M1, asecond transistor M2, and a storage capacitor Cst.

The first transistor M1 may be connected between the qth data line Dqand the second transistor M2.

For example, a gate electrode of the first transistor M1 may beconnected to the pth scan line Sp, a first electrode of the firsttransistor M1 may be connected to the qth data line Dq, and a secondelectrode of the first transistor M1 may be connected to a gateelectrode of the second transistor M2.

The first transistor M1 may be turned on when the scan signal issupplied to the pth scan line Sp, to supply a data signal from the qthdata line Dq to the storage capacitor Cst.

In an embodiment, the storage capacitor Cst may charge a voltagecorresponding to the data signal.

The second transistor M2 may be connected between the first power sourceELVDD and the organic light emitting diode OLED.

For example, the gate electrode of the second transistor M2 may beconnected to a first electrode of the storage capacitor Cst and thesecond electrode of the first transistor M1, a first electrode of thesecond transistor M2 may be connected to a second electrode of thestorage capacitor Cst and the first power source ELVDD, and a secondelectrode of the second transistor M2 may be connected to the anodeelectrode of the organic light emitting diode OLED.

The second transistor M2 is a driving transistor, and may control theamount of current flowing from the first power source ELVDD to thesecond power source ELVSS via the organic light emitting diode OLED,corresponding to a voltage value stored in the storage capacitor Cst.

In an embodiment, the organic light emitting diode OLED may generatelight corresponding to the amount of current supplied from the secondtransistor M2.

Here, the first electrode of each of the transistors M1 and M2 may beset as any one of a source electrode and a drain electrode, and thesecond electrode of each of the transistors M1 and M2 may be set as anelectrode different from the first electrode. For example, if the firstelectrode is set as a source electrode, the second electrode may be setas a drain electrode.

In an embodiment, a case where the transistors M1 and M2 are PMOStransistors is illustrated in FIG. 13 . However, in another embodiment,the transistors M1 and M2 may be implemented as NMOS transistors.

The above-described pixel structure of FIG. 13 is merely an embodiment,and the pixel 410 is not limited to the pixel structure. Actually, thepixel 410 may have a circuit structure in which current can be suppliedto the organic light emitting diode OLED, and be selected as any one ofvarious structures currently known in the art.

The first power source ELVDD may be a high-potential power source, andthe second power source ELVSS may be a low-potential power source.

For example, the first power source ELVDD may be set to a positivevoltage, and the second power source ELVSS may be set to a negativevoltage or a ground voltage.

FIG. 14 is a view illustrating the display device according to theembodiment.

Referring to FIG. 14 , the display device 2 according to the embodimentmay further include touch electrodes 110, a demultiplexer 200 a and 200b, and driving pads 310.

The touch electrodes 110 may be located on the encapsulation layer 420.As described above, the touch electrodes 110 may constitute a pluralityof electrode groups 101, 102, 103, and 104, and electrode units 100.

The demultiplexer 200 a and 200 b may be located on the second region A2of the substrate 10. In an embodiment, the demultiplexer 200 a and 200 bmay selectively connect the touch electrodes 110 electrically to thedriving pads 310.

In an embodiment, in order to efficiently use the non-display region,one portion 200 a of the demultiplexer 200 a and 200 b may be disposedat a first side of the display driver 430, and the other portion of thedemultiplexer 200 a and 200 b may be disposed at a second side of thedisplay driver 430 that is opposite the first side of the display driver430. According to the above-described configuration, the total area ofunnecessary dead spaces (i.e., areas not used for displaying images orreceiving touches) can be minimized.

For example, some of the first demultiplexers 210 and some of the seconddemultiplexers 220 may be located at the first side of the displaydriver 430, and other first demultiplexers 210 and other seconddemultiplexers 220 may be located at the second side of the displaydriver 430.

In an embodiment, some of the third demultiplexers 230 and some of thefourth demultiplexers 240 may be located at the first side of thedisplay driver 430, and other third demultiplexers 230 and other fourthdemultiplexers 240 may be located at the second side of the displaydriver 430.

In an embodiment, the display device 2 according to the embodiment mayfurther include a connecting member 450 and a touch driving unit 460.

The connecting member 450 may be attached to the driving pads 310, andthe touch driving unit 460 may supply driving signals to the drivingpads 310 through the connecting member 450. In an embodiment, the touchdriving unit 460 may be mounted on the connecting member 450.

FIGS. 15A and 15B are cross-sectional views taken along line A-A′ ofFIG. 14 according to one or more embodiments, and FIG. 15C is across-sectional view taken along line B-B′ of FIG. 14 according to anembodiment.

Referring to FIG. 15A, the organic light emitting diode OLED accordingto the embodiment may include a first electrode 511, an emitting layer512, and a second electrode 513.

The emitting layer 512 may be located between the first electrode 511and the second electrode 513. In an embodiment, the first electrode 511and the second electrode 513 may serve as an anode electrode and acathode electrode, respectively.

For example, the emitting layer 512 may preferably include an organicemission layer for self-luminescence.

In an embodiment, the emitting layer 512 may be formed in a structure inwhich a hole transporting layer, the organic emission layer, and anelectron transporting layer are stacked. In an embodiment, the emittinglayer 512 may further include a hole injection layer and an electroninjection layer.

According to the above-described structure, holes injected from thefirst electrode 511 and electrons injected from the second electrode 513are combined in the organic emission layer to form excitons, and lighthaving a specific wavelength is generated from each emitting layer 512by energy from the formed excitons.

In an embodiment, a plurality of pixels 410 may be located on thesubstrate 10. In an embodiment, each pixel 410 may be configured with apixel circuit (not shown) including a driving transistor Tr and theorganic light emitting diode OLED.

For convenience of description, only the driving transistor Tr directlyrelated to the organic light emitting diode OLED is illustrated in FIGS.15A and 15B. However, in order to control emission of the organic lightemitting diode OLED, the pixel circuit (not shown) may be additionallyprovided with another transistor, a capacitor, and the like, in additionto the driving transistor Tr.

A buffer layer (not shown) for preventing diffusion of impuritiescontained in the substrate 10 may be located on the substrate 10. In anembodiment, the buffer layer may be formed in a single- or multi-layeredstructure.

The driving transistor Tr may be formed on the substrate 10. The drivingtransistor Tr may be formed corresponding to each organic light emittingdiode OLED.

The driving transistor Tr may include a gate electrode 510, a gateinsulating layer 520, a semiconductor layer 530, and source/drainelectrodes 540 a and 540 b.

The gate electrode 510 may be formed on the substrate 10.

The gate insulating layer 520 may be formed over the gate electrode 510.For example, the gate insulating layer 520 may be formed of aninsulating material such as silicon oxide (SiOx) or silicon nitride(SiNx).

The semiconductor layer 530 may be formed on the gate insulating layer520. For example, the semiconductor layer 530 may be formed ofpoly-silicon obtained by crystallizing amorphous silicon using laser,etc.

In an embodiment, the semiconductor layer 530 may be formed of amorphoussilicon, oxide semiconductor, etc., in addition to the poly-silicon.

The source/drain electrodes 540 a and 540 b may be located at both sidesof the semiconductor layer 530, respectively.

A planarization layer 550 may be located over the driving transistor Tr,and be provided with a contact hole 560 that exposes the sourceelectrode 540 a or the drain electrode 540 b. In FIGS. 15A and 15B, acase where the drain electrode 540 b is exposed through the contact hole560 is illustrated as an example.

The gate electrode 510 and the source/drain electrodes 540 a and 540 bmay be formed of a metal such as molybdenum (Mo), tungsten (W), titanium(Ti), or aluminum (Al), an alloy thereof, or a stack structure thereof,but the present disclosure is not limited thereto.

In an embodiment, the driving transistor Tr is not limited to thestructure shown in FIGS. 15A and 15B, and may be modified to haveanother structure. For example, the transistor Tr having a bottom gatestructure is illustrated in FIGS. 15A and 15B, but may be modified tohave a top gate structure.

The first electrode 511 is formed on the planarization layer 550, andmay be connected to the source electrode 540 a or the drain electrode540 b through the contact hole 560. In FIGS. 15A and 15B, a case wherethe first electrode 511 is connected to the drain electrode 540 bthrough the contact hole 560 is illustrated as an example.

For example, the planarization layer 550 may be formed of an insulatingmaterial such as silicon oxide or silicon nitride.

A pixel defining layer 570 may be located on the planarization layer550. In an embodiment, the pixel defining layer 570 may define positionsof the organic light emitting diodes OLED.

In an embodiment, the pixel defining layer 570 may expose at least apartial region of the first electrode 511.

In an embodiment, a plurality of openings 571 may exist in the pixeldefining layer 570, and the first electrodes 511 of the organic lightemitting diodes OLED may be exposed through the openings 571,respectively.

For example, the pixel defining layer 570 may be made of one of organicinsulating materials such as acryl-based organic compound, polyamide,and polyimide. However, the present disclosure is not limited thereto,and the pixel defining layer 570 may be formed of various insulatingmaterials.

In an embodiment, as described above, the emitting layer 512 and thesecond electrode 513 may be sequentially disposed on the first electrode511.

In an embodiment, the second electrode 513 may extend along the pixeldefining layer 570 to be connected to the second electrode 513 of anadjacent organic light emitting diode OLED. In an embodiment, the secondelectrodes 513 of the organic light emitting diodes OLED may beconnected to each other.

As a result, the pixel defining layer 570 may define positions of theorganic light emitting diodes OLED through the openings 571 thatdetermine positions of the first electrodes 511.

The encapsulation layer 420 may be located over the organic lightemitting diodes OLED. Specifically, the encapsulation layer 420 may belocated over the second electrodes 513.

Referring to FIG. 15B, the display device 2 according to the embodimentmay further include a buffer layer 590 located on the encapsulationlayer 420. In an embodiment, the touch electrodes 110 may be located onthe buffer layer 590.

The buffer layer 590 may be disposed to minimize damage of theencapsulation layer 420 and the organic light emitting diode OLED whenthe touch electrodes 110 are formed.

For example, the buffer layer 590 may include an inorganic insulatingmaterial and an organic insulating material. However, the buffer layer590 may be integrated with the encapsulation layer 420 or be omitted, ifnecessary.

Referring to FIG. 15C, the driving pad 310 according to the embodimentmay include a first conductive pattern 311 and a second conductivepattern 312.

The first conductive patter 311 may be located on the substrate 10, andan insulating layer 421 having a contact hole 422 may be located overthe first conductive pattern 311.

The insulating layer 421 may be formed through the same process as theabove-described encapsulation layer 420, and have the same structure asthe encapsulation layer 420.

The second conductive pattern 312 may be located on the insulating layer421, and be in contact with the first conductive pattern 311 through thecontact hole 422.

For example, the second conductive patter 312 may be electricallyconnected to the demultiplexer 200 a and 200 b through a line (notshown) located on the insulating layer 421.

In an embodiment, the connecting member 450 may be attached on thesecond conductive pattern 312, to perform electrical connection betweenthe driving pad 310 and the touch driving unit 460.

FIGS. 16A and 16B are views illustrating display devices according toembodiments.

Referring to FIG. 16A, in a display device 2′ according to anembodiment, a touch driving unit 460′ may be located on the secondregion A2 of the substrate 10.

In an embodiment, the touch driving unit 460′ may be integrated with theabove-described demultiplexer 200 to be implemented in one integratedcircuit (IC).

In an embodiment, the driving pads 310 and the demultiplexer 200 builtin the touch driving unit 460′ may function to supply driving signals Dsto the touch electrodes 110 in a test process before product shipment.However, when the display device 2′ is actually used after productcompletion, the touch driving unit 460′ may directly supply the drivingsignals Ds to the touch electrodes 110 without passing through thedemultiplexer 200. Therefore, when the display device 2′ is actuallyused, the operation of the demultiplexer 200 may be stopped.

In an embodiment, driving lines 480 connected to the touch electrodes110 may be gathered at an upper side of the bending region BA toconstitute one group, and be connected to the touch driving unit 460′ bycrossing the bending region BA.

In an embodiment, the total area of dead spaces can be minimized.

Referring to FIG. 16B, in a display device 2″ according to anembodiment, driving lines 480 a and 480 b connected to the touchelectrodes 110 may constitute a plurality of groups.

In an embodiment, some driving lines 480 a may be gathered at an upperside of the bending region BA to constitute one group, and be connectedto the touch driving unit 460′ by crossing the bending region BA.

In an embodiment, other driving lines 480 b may be gathered at an upperside of the bending region BA to constitute another group, and beconnected to the touch driving unit 460′ by crossing the bending regionBA and then passing through a path between the bending region BA and thedisplay driver 430.

In an embodiment, the total area of dead spaces can be minimized.

According to embodiments, it is possible to minimize the number of padsin a touch sensor and/or a display device.

Example embodiments have been disclosed. Although specific terms areemployed, they are used and are to be interpreted in a generic anddescriptive sense and not for purpose of limitation. In some instances,features, characteristics, and/or elements described in connection witha particular embodiment may be used singly or in combination withfeatures, characteristics, and/or elements described in connection withother embodiments unless otherwise specifically indicated. Variouschanges in form and details may be made to the example embodimentswithout departing from the spirit and scope as set forth in thefollowing claims.

What is claimed is:
 1. A display device comprising: a substrate; a pixelarray disposed on the substrate and comprising a plurality of pixels; atouch electrode array disposed on the pixel array and comprisingelectrode groups each including touch electrodes arranged in a firstdirection; a first demultiplexer disposed on the substrate andelectrically connected to the touch electrode array, the firstdemultiplexer including sub-demultiplexers electrically connected to theelectrode groups; a driving pad disposed on the substrate; and a seconddemultiplexer disposed on the substrate and electrically connectedbetween the first demultiplexer and the driving pad.
 2. The displaydevice of claim 1, wherein the electrode groups comprise a firstelectrode group and a second electrode group adjacent to each other in asecond direction intersecting the first direction.
 3. The display deviceof claim 1, wherein the electrode groups comprise a first electrodegroup and a second electrode group adjacent to each other in the firstdirection.
 4. The display device of claim 1, wherein: the pixel arrayand the touch electrode array are disposed in a first region of thesubstrate, and wherein the first demultiplexer, the seconddemultiplexer, and the driving pad are disposed in a second region ofthe substrate positioned at a side of the first region.
 5. The displaydevice of claim 4, wherein the sub-demultiplexers are adjacent to eachother in a second direction intersecting the first direction.
 6. Thedisplay device of claim 1, wherein: the electrode groups comprise afirst electrode group and a second electrode group; and thesub-demultiplexers comprises a first sub-demultiplexer and a secondsub-demultiplexer electrically connected to the first electrode groupand the second electrode group, respectively.
 7. The display device ofclaim 1, wherein: the electrode groups comprise first and secondelectrode groups adjacent to each other in a second directionintersecting the first direction, a third electrode group adjacent tothe first electrode group in the first direction, and a fourth electrodegroup adjacent to the second electrode group in the first direction; andthe sub-demultiplexers comprises first to fourth sub-demultiplexerselectrically connected to the first to fourth electrode groups,respectively.
 8. The display device of claim 1, further comprising: afirst voltage pad to provide a first voltage; and a third demultiplexerelectrically connected between the touch electrode array and the firstvoltage pad.
 9. The display device of claim 8, wherein the thirddemultiplexer comprises sub-demultiplexers electrically connected to theelectrode groups, respectively. 10
 10. The display device of claim 8,further comprising: a second voltage pad to provide a second voltagedifferent from the first voltage; and a fourth demultiplexerelectrically connected between the touch electrode array and the secondvoltage pad.
 11. The display device of claim 10, wherein the fourthdemultiplexer comprises sub-demultiplexers electrically connected to theelectrode groups, respectively.
 12. The display device of claim 1,further comprising: a connecting member electrically connected to thedriving pad; and a touch driver to supply a driving signal to thedriving pad through the connecting member.
 13. The display device ofclaim 1, wherein: the first demultiplexer is configured to operate inresponse to first control signals; and the second demultiplexer isconfigured to operate in response to second control signals.
 14. Thedisplay device of claim 13, further comprising: first control padsdisposed on the substrate and configured to provide the first controlsignals to the first demultiplexer; and second control pads disposed onthe substrate and configured to provide the second control signals tothe second demultiplexer.
 15. The display device of claim 1, furthercomprising an encapsulation layer disposed on the pixel array andcomprising an organic layer and an inorganic layer, wherein the touchelectrode array is disposed on the encapsulation layer.
 16. The displaydevice of claim 1, wherein the plurality of pixels comprises organiclight emitting diodes.